After work under the playfield, the coil that returns the ball from the chute under the T-Rex fires every few seconds and won't stop, even with no ball there.
Ball return kicker keeps firing every few seconds: switch bent closed
Cause: The switch that tells the game a ball is waiting had been bent so it stayed closed, and a wire at the coil had come off during the earlier repair.
Checks
- In switch test, see whether the kicker's ball switch shows closed with no ball present.
- Look for loose wires near the coil; a loose wire usually belongs with the other wire of the same colour.
Fix
- Straighten and adjust the switch so it only closes with a ball.
- Solder the loose wire back next to the same-coloured wire, checking against the manual.
Systems
Games
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Source: Pinball Repair help group!! (Facebook group)